The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 31, 2002
Filed:
Jun. 12, 2001
Applicant:
Inventor:
Kenichi Hayashi, Kanagawa, JP;
Assignee:
Sumitomo Heavy Industries, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
B41J 2/435 ;
U.S. Cl.
CPC ...
B41J 2/435 ;
Abstract
A method for observing marks includes the steps of irradiating illumination light onto a transparent substrate from one end surface thereof, the transparent substrate bearing marks constituted by cracks formed in the inner portion thereof, and observing the light scattered by the marks on one side of the transparent substrate. In the step of observing the light scattered by the marks, a black plate-shaped material or a black body is placed on the other side of the transparent substrate so that the black plate-shaped material or the black body covers a field of view of a light receiver.